排序方式: 共有47条查询结果,搜索用时 15 毫秒
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研究了交联型聚氨酯材料集成衰减全反射型双通道聚合物波导电光调制器的制备和性能。这种电光调制器的制备技术非常简单,只要用两个分立的下电极代替单通道调制器中的下电极即可。通过测量器件的调制特性,在832 nm波长下,获得了最大电光系数为24.2 Pm/V,调制带宽约为500 MHz、插入损耗低于1.5 dB。由于器件上下电极的垂直距离为微米级、而通道之间的水平距离为毫米量级的设计,使各通道之间的场不会引起相互交迭,因而未测到各通道间的串扰。另外,热交联型聚合物材料的采用提高了整个器件的热稳定性,在100℃经过800 h后,电光系数仍然保持初值的88%。 相似文献
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Photon tunneling and transmittance resonance through a multi-layer structure with a left-handed materialvspace2pt 下载免费PDF全文
This paper investigates the photon tunneling and transmittance resonance through a multi-layer structure including a left-handed material(LHM). An analytical expression for the transmittance in a five-layer structure is given by the analytical transfer matrix method. The transmittance is studied as a function of the refractive index and the width of the LHM layer. The perfect photon tunneling results from the multi-layer structure, especially from the relation between the magnitude of the refractive index and the width of the LHM layer and those of the adjoining layers. Photons may tunnel through a much greater distance in this structure. Transmittance resonance happens, the peaks and valleys appear periodically at the resonance thickness. For an LHM with inherent losses, the perfect transmittance is suppressed. 相似文献
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We investigate guided modes in the asymmetric waveguide structure with a left-handed material (LHM) layer surrounded by air and metal. A graphical method is proposed to determine the guided modes. New properties of the oscillating and surface guided modes, such as absence of the fundamental mode, coexistence of the oscillating and surface guided modes, fast attenuation of the surface guided modes, and mode degeneracy, are analyzed in detail. We also investigate dispersive characteristics of the metal-LHM- air optical waveguide. The propagation constant increases with decreasing slab thickness for the first-order oscillating mode, which is different from that in traditional metal-cladding waveguides. 相似文献
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重离子碰撞中原子核阻止的同位旋效应 总被引:1,自引:0,他引:1
利用含有3种对称势形式的同位旋相关的量子分子动力学,研究了中能重离子碰撞中原子核阻止的同位旋效应和随入射道条件的系统演化过程.计算结果表明,原子核阻止灵敏地依赖束流能量、碰撞参数、碰撞系统的质量和核子–核子碰撞截面的同位旋相关性,而3种对称势和碰撞系统的中质比对它的影响不很明显,但在大约费米能量以下能区,原子核阻止同时依赖于介质中核子–核子碰撞截面和对称势.故认为在费米能量以上能区直至150MeV/u,原子核阻止是提取介质中核子–核子碰撞截面的一个新的物理观测量. 相似文献
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A detailed procedure based on an analytical transfer matrix
method is presented to solve bound-state problems. The derivation is
strict and complete. The energy eigenvalues for an arbitrary
one-dimensional potential can be obtained by the method. The
anharmonic oscillator potential and the rational potential are two
important examples. Checked by numerical techniques, the results for
the two potentials by the present method are proven to be exact and
reliable. 相似文献
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依据角向偏振涡旋光束强聚焦有径向分量的结论,修正了角向偏振涡旋光束的强聚焦场公式,重新研究了高阶角向偏振拉盖尔高斯涡旋光束经过衍射光学元件和高数值孔径透镜后的强聚焦特性。结果发现,在焦平面附近获得了新的三维三光链结构(沿着光轴方向的一条三维主光链和对称的两条三维傍轴次光链),详细分析了入射光束缔合拉盖尔多项式的径向模数和光束的拦截比、衍射光学元件结构和聚焦系统的数值孔径对三光链的影响。结果表明,径向模数的改变会破坏三光链结构,通过调控衍射光学元件结构和拦截比可以重新获得对称性更高的三光链结构,从而实现对三光链结构的高自由度调控。 相似文献
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